Thread milling ?

Well, I'm pleased to report that things went alright... I didn't video my mill doing the deed, so to speak, but the results are below - you can see how I modified the tap in the second clip. Turns out I didn't need to feed in tangentially, I'm coming in from above so it makes no real difference... It's a decent fit but was a little tight to begin with - nothing that running the nut over didn't sort, though.

I'm quite chuffed with the results here - but yeah, of course, it's a hack. CZ121 is forgiving and I wouldn't fancy the chances of this going as well on something harder..! Certainly gets me out of a hole for a little project I've got on the go at the moment.

https://youtu.be/b8TnfNiuA9A

Wal.

EDIT - in action:

https://youtu.be/tV-9vug1Ke8

Nice!

Wal Great job.:applouse: who would have though it.